Differences in Decline in the Subcomponents of the Unity-Diversity Model of Executive Functioning between Younger and Older Adults: A Meta Analysis

Declines in fluid cognitive processes, including executive function (EF), occur in advanced age. Impaired EF can result in poor control of behavior and failure to achieve goals, negatively impacting quality of life for older adults (OA). Research using factor analysis has divided EF into 3 subcomponents—inhibition, set shifting, and updating—and these components are seen in both OA and young adults (YA). Subsequent work examining these three domains individually, however, does not always show age-related performance declines in EF subcomponents. Thus, examining these EF components in advanced age is of interest, as the subcomponents may be differentially impacted by aging, and may provide important targets for cognitive remediation. To investigate age-differences in the EF subcomponents associated with the unity-diversity model, we conducted a meta-analysis. We expect overall declines in EF in OA with specific declines in set shifting and updating; but age-related declines in inhibition are not likely to be as prominent. Further, all these declines might be influenced by processing speed changes. Using 229 effect sizes from 31 articles we found overall declines in EF with age. Additional subgroup analyses, using processing speed as a moderator, suggests that age negatively impacts EF for each subgroup and processing speed moderates this decline. Thus, future research should examine how specific interactions between these subgroups cause EF decline and further examine the influence of processing speed as a moderating factor in these interactions. This understanding can directly inform cognitive remediation procedures and early detection of EF decline.